Unilateral mydriasis: a complication of spine surgery in prone position

Prone position though is commonly used for better access to surgical site, but may be associated with a variety of complications. Perioperative Visual Disturbances or loss is rare but a devastating complication that is primarily associated with spine surgeries in prone position. In this case we report a 42 year old ASA-II patient who developed anisocoria with left pupillary dilatation following lumbar microdiscectomy in prone position. Following further evaluation of the patient, segmental pupillary palsy of the left pupillary muscles was found to be the possible cause of anisocoria. Anisocoria partially improved but persisted till follow up.